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-rw-r--r--kernel/arch/x86/include/asm/syscall.h243
1 files changed, 243 insertions, 0 deletions
diff --git a/kernel/arch/x86/include/asm/syscall.h b/kernel/arch/x86/include/asm/syscall.h
new file mode 100644
index 000000000..d6a756ae0
--- /dev/null
+++ b/kernel/arch/x86/include/asm/syscall.h
@@ -0,0 +1,243 @@
+/*
+ * Access to user system call parameters and results
+ *
+ * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * See asm-generic/syscall.h for descriptions of what we must do here.
+ */
+
+#ifndef _ASM_X86_SYSCALL_H
+#define _ASM_X86_SYSCALL_H
+
+#include <uapi/linux/audit.h>
+#include <linux/sched.h>
+#include <linux/err.h>
+#include <asm/asm-offsets.h> /* For NR_syscalls */
+#include <asm/thread_info.h> /* for TS_COMPAT */
+#include <asm/unistd.h>
+
+typedef void (*sys_call_ptr_t)(void);
+extern const sys_call_ptr_t sys_call_table[];
+
+/*
+ * Only the low 32 bits of orig_ax are meaningful, so we return int.
+ * This importantly ignores the high bits on 64-bit, so comparisons
+ * sign-extend the low 32 bits.
+ */
+static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
+{
+ return regs->orig_ax;
+}
+
+static inline void syscall_rollback(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ regs->ax = regs->orig_ax;
+}
+
+static inline long syscall_get_error(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ unsigned long error = regs->ax;
+#ifdef CONFIG_IA32_EMULATION
+ /*
+ * TS_COMPAT is set for 32-bit syscall entries and then
+ * remains set until we return to user mode.
+ */
+ if (task_thread_info(task)->status & TS_COMPAT)
+ /*
+ * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
+ * and will match correctly in comparisons.
+ */
+ error = (long) (int) error;
+#endif
+ return IS_ERR_VALUE(error) ? error : 0;
+}
+
+static inline long syscall_get_return_value(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return regs->ax;
+}
+
+static inline void syscall_set_return_value(struct task_struct *task,
+ struct pt_regs *regs,
+ int error, long val)
+{
+ regs->ax = (long) error ?: val;
+}
+
+#ifdef CONFIG_X86_32
+
+static inline void syscall_get_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ unsigned long *args)
+{
+ BUG_ON(i + n > 6);
+ memcpy(args, &regs->bx + i, n * sizeof(args[0]));
+}
+
+static inline void syscall_set_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ const unsigned long *args)
+{
+ BUG_ON(i + n > 6);
+ memcpy(&regs->bx + i, args, n * sizeof(args[0]));
+}
+
+static inline int syscall_get_arch(void)
+{
+ return AUDIT_ARCH_I386;
+}
+
+#else /* CONFIG_X86_64 */
+
+static inline void syscall_get_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ unsigned long *args)
+{
+# ifdef CONFIG_IA32_EMULATION
+ if (task_thread_info(task)->status & TS_COMPAT)
+ switch (i) {
+ case 0:
+ if (!n--) break;
+ *args++ = regs->bx;
+ case 1:
+ if (!n--) break;
+ *args++ = regs->cx;
+ case 2:
+ if (!n--) break;
+ *args++ = regs->dx;
+ case 3:
+ if (!n--) break;
+ *args++ = regs->si;
+ case 4:
+ if (!n--) break;
+ *args++ = regs->di;
+ case 5:
+ if (!n--) break;
+ *args++ = regs->bp;
+ case 6:
+ if (!n--) break;
+ default:
+ BUG();
+ break;
+ }
+ else
+# endif
+ switch (i) {
+ case 0:
+ if (!n--) break;
+ *args++ = regs->di;
+ case 1:
+ if (!n--) break;
+ *args++ = regs->si;
+ case 2:
+ if (!n--) break;
+ *args++ = regs->dx;
+ case 3:
+ if (!n--) break;
+ *args++ = regs->r10;
+ case 4:
+ if (!n--) break;
+ *args++ = regs->r8;
+ case 5:
+ if (!n--) break;
+ *args++ = regs->r9;
+ case 6:
+ if (!n--) break;
+ default:
+ BUG();
+ break;
+ }
+}
+
+static inline void syscall_set_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ const unsigned long *args)
+{
+# ifdef CONFIG_IA32_EMULATION
+ if (task_thread_info(task)->status & TS_COMPAT)
+ switch (i) {
+ case 0:
+ if (!n--) break;
+ regs->bx = *args++;
+ case 1:
+ if (!n--) break;
+ regs->cx = *args++;
+ case 2:
+ if (!n--) break;
+ regs->dx = *args++;
+ case 3:
+ if (!n--) break;
+ regs->si = *args++;
+ case 4:
+ if (!n--) break;
+ regs->di = *args++;
+ case 5:
+ if (!n--) break;
+ regs->bp = *args++;
+ case 6:
+ if (!n--) break;
+ default:
+ BUG();
+ break;
+ }
+ else
+# endif
+ switch (i) {
+ case 0:
+ if (!n--) break;
+ regs->di = *args++;
+ case 1:
+ if (!n--) break;
+ regs->si = *args++;
+ case 2:
+ if (!n--) break;
+ regs->dx = *args++;
+ case 3:
+ if (!n--) break;
+ regs->r10 = *args++;
+ case 4:
+ if (!n--) break;
+ regs->r8 = *args++;
+ case 5:
+ if (!n--) break;
+ regs->r9 = *args++;
+ case 6:
+ if (!n--) break;
+ default:
+ BUG();
+ break;
+ }
+}
+
+static inline int syscall_get_arch(void)
+{
+#ifdef CONFIG_IA32_EMULATION
+ /*
+ * TS_COMPAT is set for 32-bit syscall entry and then
+ * remains set until we return to user mode.
+ *
+ * TIF_IA32 tasks should always have TS_COMPAT set at
+ * system call time.
+ *
+ * x32 tasks should be considered AUDIT_ARCH_X86_64.
+ */
+ if (task_thread_info(current)->status & TS_COMPAT)
+ return AUDIT_ARCH_I386;
+#endif
+ /* Both x32 and x86_64 are considered "64-bit". */
+ return AUDIT_ARCH_X86_64;
+}
+#endif /* CONFIG_X86_32 */
+
+#endif /* _ASM_X86_SYSCALL_H */